Radar antenna structure



y 13, 1952 w. w. LINDSAY, JR 2,596,966

RADAR ANTENNA STRUCTURE Filed Nov. 16, 1948 3 Sheets-Sheet l "huh...

w. w. LINDSAY, JR

RADAR ANTENNA STRUCTURE May 13, 1952 3 Sheets-Sheet 2 Filed Nqv. 16. 1948 Jfdlilmn/WJ" Patented May 13, 1952 RADAR ANTENNA STRUCTURE I William W. Lindsay, Jr., Los Angeles, Calif., as-

signor to Gilfillan Bros}, Inc., Los Angeles, Calif., a corporation of California Application November 16, 1948, Serial No. 60,325

'1 The present invention relates to an improved variable cross-section wave guide arrangedto feed a plurality of dipoles in, for example and structure of the type described in the abovementioned patent application, it is of importance that the cross-sectional dimensions of the wave guide at various sections along the wave guide may be adjusted independently and easily in order to efiect a sharply directed 'electro magnetic radiated beam. Such adjustment consists in adjusting what is termed in the art as the a dimension and b clearance. It has been observed that not only must the a dimension be adjusted precisely but also the b clearance must also be adjusted precisely to produce the intended sharply directed beam. It is, therefore, desirable that substantially independently operated means be provided and spaced along the wave guide to adjust independently and continuously the corresponding 0. dimension and b clearance to thereby adjust the cross-sectional dimensions and resulting sharpness and freedom from side lobes of the radiated beam.

In accordance with the present invention, not only is the adjustment of such a dimension continuous over a range but also the ad usting means for the b clearance is likewise adjusted continuously over a range.

One of the objects of the present invention is to provide improved adjusting means whereby both the a dimension and b clearance may be continuously varied over a range to facilitate adjustment of the antenna structure proper.

A specific object of the present invention is to provide an improved adjustable mounting for a wave guide member such that the 1) clearance may be adjusted continuously over a range.

Another object of the present invention is to provide an improved Wave guide which is relatively easy to manufacture, assemble and to maintain in working condition and characterized by the ease with which the a dimension and b clearance may be varied continuously over a range.

Yet another object of the present invention is Claims. (01. o ss.63)

to provide an improved antenna wave guide structure characterized by the fact that various portions of the guide may be adjusted independently of other portions and continuously in two mutually perpendicular directions whereby the wave guide may be adjusted for uniform or non-uniform dimensions, as the case may be, throughout its length for achievement of the desired radiation characteristics.

A further object of the present invention is to provide an improved cross-sectional wave guide characterized by the ease with which the a dimen ion and b clearance thereof may be conveniently adusted continuously over a range at various sections along the wave guide, a subsidiary feature being that the wearing surfaces are readily accessible and interchangeable whereby the wave guide may be conveniently serviced while in use in the field.

Yet another object of the present invention is to provide an improved variable cross-section wave guide having one movable element thereof continuously adjustable in two mutually perpendicular directions at different regions along its length whereby the cross-section may be adjusted to produce the desired radiation characteristics.

Yet another obieot of the present invention is to provide an improved variable cross-section wave guide characterized by the comparative ease with which the a dimension and/or b clearance may both be adjusted continuously over a range.

Still another object of the present invention is to provide an improved variable cross-section wave guide comprising a movable wave guide member and a relatively stationary wave guide member characterized by the fact that by removing conveniently accessible bridge supporting members, the interior of the wave guide may be conveniently inspected and cleaned, and thereafter such supporting bridge members mounted in place again without disturbing appreciably the initial a dimension and/or 1) clearance adjustment of the wave guide, and also by the fact that such a dimension and b clearance may both be adjusted continuously over a range of values.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. This invention itselhboth as to its organization and manner of operation, together with further objects and advantages thereof, may be best understood by reference to the following description taken in con- Figures 4, 5 and 6 are perspective views of the various elements incorporated inthe. :.St ?uQtures.-

shown in the previous three figures.

Figure 7 is a cross-sectional-view,similar-to .1

the cross-sectional view shown-in Figure-1 but;

taken through different spaced sections of the wave guide antenna structureto ,iillustrate $113 manner in which the a dimension is continuously adjustable over a range of values.

Figure 8 is a plan View of the variable cross-sectional wave guide within which the :present inventionis incorporated.

Figure 9 isa sectional view through a portion of the wave guide structure.

Figure 10 is a sectional 'view-taken-substantially on the line 10-40 of Figure 9;

Figuresll is another sectional view taken through "the antenna structure. r

Figure 12 is a view inelevation'showing the other side. of the. wave guide; shown'in Figure 8.

As mentioned hereinabove,;;the present invention. relates-to improvements in the bridge-type precision antenna structure described and claimed in- .theco mending patent; application of Karl-:A- Allebach,ySerlal N02; 4,931.0:-

For- :a 31110136 .completedescription of; the, antenna structure, reference.v may her-had to such coependin'g application,v and the. structure shown and described thereinis:incorporatedherein by reference and is deemed; to;be:inc lud e d herein as ifiset forth. herein-tat. leng-tln; For -;this purpose, and .for convenience of; reference, the same elementsiin. the present applicationzand in the aforementioned. cO-pending application have identical reference numerals- The variable cross-section waveguide comprises essentially two parts, namely, a relatively stationary member 10 and a relatively movable member l l, the member H being reciprocable in these-called ,a dimension or in the direction indicated by thearrows 1'3. in Figure '7 to maintain the; internal variable cross-sectional area 14 of the wave guide rectangular at all times. This socalledf-cr dimension is the distance, in Figure 7, between the walls-NB, MB of the cooperating Wave guide members -I!l, H. This a dimension, of'course, varies with variation in position ofthe movable wave guide member I l.

The movable wave guide member II is so supported that it is adjustable atdifierent positions along its length in two mutuallyperpendicular directionscorrespondingto the axes of the rectangular area 14 to assure substantially the same or difierent cross-sectional area along-the length of: the guide. The manner in which such memher ll is adjustablysupportedto produce this result is of importance in the action describedin detail hereinafter. Also, since the movable element ll' isrelatively long and heavy it must have suitable bearing surfaces which, in accordance with one of the ieatures ofthe: present inventicn.;a eil ces bl n s y p able in the .field,

As shown in Figure 37, the wave 1 guide area is defined. onithe- One. han y p pendi ul r flQ NBA, lilB on the stationary member ID and on the other hand by the perpendicular faces HA, B on the movable member II.

Face HJB comprises one of the surfaces of an integrally formed flange l8 on the channel shaped member ID, the flange l8 having a slotted portion ISA one quarter guide wave length deep which .extends the fullilengt hoftheiflange l8 and cooperateswith the adjacently positioned leg I I0 to form a choke to prevent the leakage of radio frequency energy which would otherwise flow throughitheso-called .b clearance or clearance space 20 between flange l8 and leg NC. The clearances 20,52 is (Figure 7) are referred to herein'asthe b clearances, and are the spacing between cooperating L-shaped portions of the guide members lib-J1, :as, shown in Figure 7, such cooperating L-shaped' portions of the guide members My having an end of a leg of one L-shaped portion spaced from the adjacent leg of the other cooperating portion by .a mstar-ice. termed 'herein as .the :fb? clearance: wand; represented "by the nacinsuor c1earances..20w2- In similar manner, -,-face, 4 IB comprises one; of the surfaces-of:the: L-shaped movab-lewave guide member .1 t, rmembeni 1 having :a slotted portion i ll) one yquartertrguidei Wave -'length deep; which extends theyfuli length .of the. member 41 and cooperates with .ethe. adjacently positionedeface 1 0A to forma choke-to prevent the zleakage-of radio frequency energy which would otherwise-flow throughgthez other-.so-called :b. clearance or clearance. space-21: between-member .l landiface 19A. h rpu r' cseof moving-.thewaveguidemember H- with. respect; to the. other -.wave uide m n herq!!! is to1.alter-.ithe;;phase velocity and-hence the: Wave. length in. the guide to :thereby: change the relatise p iaseyat which rthe dipoles 25 are fed; I This changein phase-alters thaefiective-direction or the ,zcombi-ned. radiatedwave i front, or beainwith cthe, result.-.that...such beam scans through space whenthe-wave. guide member II is moved. A reflector .39., :havingan =.L-shapedcrosssection is mounted onthe guide vinember. :10.- with its axisparailel to the-axis parallel to the array-of dipolesr25 The wave guide members 48, .1 lmay be-approximately fourteen feet long-or any other suitable: length to ,pr oducea radiation beam-of desired width and is intendedioruse asa so-called precision type of antenna in ground controlled approach (GCA) systems. The wave guide: memher it supports a linear broad side array of a eontinuous linelof. approximately 18.0 or any other suitablenuinber of. dipolesZS. These dipoles may besuitably spaced over a sufiicient length to produce a beam approximately-0.4?widerin-elevation. These -,dipoles-. ZS-*are; mounted along the wide. side of the; supporting waveguide member H) with their center conductors, 25A extending into: the guide: as-pickupeprobesi The insertion depth of the. individuaidipoleiprobesa25A may be varied. palongythe length ofthe array to produce a gable 'or other suitable distribution of power.

The dipole spacing .iswapproximately one-half of the guide: wave :length andmalternate dipoles are reversed thus suppressing strong lobes which would otherwise exist-at approximately45 either side of the main: lobe...

The small percentage ofrpower not-picked up by the series of probes 25A is dissipated by an attached load or conventional absorber unit 26 to prevent the formation oihigh standing .waves due to reflection which would result in producing side lobes. This absorber unit may contain a mixture of graphite and sand and may be equipped with external heat radiating fins and may be disposed at the end of the wave guide I0, I I opposite to that end to which the high fre- -'quency energy is fed.

The movable wave guide member II is supported largely by an adjustablyand releasably positioned series of bridge members 40A as required and at equal spaced positions along the wave guide. These bridge members 40A are each of the same construction and, as shown, are releasably mounted by bolts 33 on opposite inner flange members SI, 32. These bridge members each rotatably support'a pair of ball bearing members 42 on corresponding axles I43A forming a part of the adjustably positioned crank members I43. The outer surfaces, if desired, ofthese ball bearing members 42 are hardened and cooperate with the abutting hardened surfaces on the bearing plates or tracks 44, 45 mounted by means of bolts 47 on the underside of the movable wave guide member I I. of importance is the fact that these bearing members comprising the plates 44, 45 and the roller bearing members 42 are conveniently accessible from the bottom of the wave guide after the cover member 48 is removed so that as these bearing members or tracks become worn in use, they may be replaced in the field allowing the continued use of the same wave guide members II), II. In otherwords, the wave guide members I6, I I are not susceptible of wear as are prior art wave guides. This is a very desirable feature since the manufacture of such wave guide members requires much skill and great care in observing dimensions.

In accordance with the present invention, the adjustably positioned crank members I43 are useful in continuously adjusting the 1) clearance of the wave guide.

The crank member I43 comprises the shaft I43A upon which the bearing member 42 is maintained by a set screw I433, and includes also a circular shaft I430 which is clampable in the. circular apertures I45 in the bridge member 40A; also, the crank member I43 has an enlarged head I43D with a wrench socket I43E in its end for convenience in turning. The head I43D may also include an indicia marked I43F for cooperation with the dial scales I46 on the bridge member 40A.

The crank member I43 or off-set shaft is held in adjustable positions within the apertures I45 by clampin screws I 50 threaded in the bridge member 49A and passing through the clamping slots I41 therein to urge the metal forming the bottom portion of the holes I45 against the circular shaft I 43 to thereby clamp it in adjusted position.

In assembling the wave guide, the clamping screws I50 are screwed down into clampingw engagement with the indicia I43F upon the crank member I43 adjacent the 0 mark along the scales I46. Thereafter, shims 50 are interposed between the individual bridge members 40A and their supporting bridge flanges 3|, 32, the shims 50 being of such thickness that the movable wave guide II just touches the stationary wave guide member ID, in which case, the wave guide has a zero 1) clearance and, thereafter, the b clearance may be adjusted continuously to different calibrated magnitudes, as determined by the position of the indicia I43F with respect to the scales I46 on the bridge members. Such scales may be marked ofi, for example, in thousandths of an inch. To effect an adjustment in b clearance, the clamping. screw I50 is loosened and the crank member I43 is rotated the desired amount, using for that purpose a hexagonal head wrench engaged with the cooperat- 7 II only in the direction indicated by the arrows I3 (Figure '7), a centrally disposed guide block 60, strap 63, and bearings 61, 68 (Figures9 and are provided.

The constructional features of this guide bearing 60 are more clearly shown in Figures 8; 9,

10 and 12. Such guide block 60 comprises a rectangular guide block 60 releasably attached to the guide member I I by bolt 62 and a strap member 63 attached by bolts 65 to the flanges 3I, 32,

there being provided a pair of roller bearings 61, 58 rotatably and releasably mounted on a strap 63 for cooperation with the guide block 60. This guide block 60 may be hardened to resist wear as well as the outer cooperating surfaces on the guide rollers 61, 68. It is apparent that this guide block 60, comprising essentially the elements 60, B1, 68 and 63 may be conveniently replaced since all the elements are screw or boltfastened. The guide roller 61, 68 may be removed after removing their fastening nuts 61A, 683, respectively.

The wave guide member II is reciprocated in the direction indicated by arrows I3 in Figure 7 upon rotation of the motor driven shaft 10 in Figures 11 and 12, the rotary movement of shaft I0 being converted into movement of the bar II. The assembly shown in Figure 11 comprises a crank member I2 coupled to the shaft 10, an arm 13 adjustable in length and having one of its ends rotatably supported on the crank shaft I2 and the other of its ends journaled for rotation on the shaft 14 on the block 15 which is attached to the bar 'II by bolts 16, thus rotary movement of shaft I0 results in movement of the bar 1| in the direction indicated by the arrows I8 in Figure 11. Such movement of bar II along the longitudinal axis of the wave guide is converted into motion of the movable wave uide member I I in a direction transverse to the axis of the wave guide by pivotally connected pairs of link members 80, 8| located at stations A, B, C, D, E, and F or at as many stations as are required by the length of the array.

The pairs of link members 80, 8| are connected to the longitudinal movable actuating bar II as shown in Figure '7. For this purpose, a locking bolt I 00 passes through aligned apertures in the bar 'II, spacer WI, and the central core of the ball bearing member I03 in one end of link pin to lock these elements together by the releasable nut I05. The other end of link member 8| is bifurcated to receive the adjustably positioned extension 32A of flange 32. The bifurcated ends of link member BI each receive a roller bearing member I05, I06, the central cores of which are locked together and to the flange extension 32A by the bolt I09 having the fastened nut H0 thereon. Thus, the link'member 8I may rotate about the axis of the bolt I09. This axis of rotation which corresponds to the action of bolt I09 may be conveniently adjusted asrexplainedtingreaten detaithereinaiter bundiust/mentrotsthe setdscrew II:I; ifox: purposesroi addustingtheinternahff afa'dimension got. the; wave guide-Ned! The outcrglendmi' link "memberrfiiicis:provided withea ebeaizingjzinsertrzI I2, the; ;centra-lz core of whiehlisrlocked .to the, .wave: guide:.memberrII by the bolt -.-:I -I 4 :hwvingatha :fastening mut, ;:I I thereon to clamp such central core toxthenguide menrber i I: with thaspacer;l .I 6 clamped therebetween. Itaisthusapparent.that::the;mouable bar II and link assemblies; afiIl-.-:BI:rareesupported .as a;. .canti1ever;;: thesbasezsor abutment for such cantilever being zthei-zadjnstable :extension 32A ofcfflamgenlile. Incidentally; through the; intermediarymfithe linkmem-hers. 80.31; the extension 32A supports a portion of theezloadnfithe movableiwavn'guide'membeitzl I.. Y Howevergthezlarger portion-f. the. weight: of wave guide member; I I andathe: link assembly including :links: Bi); 8 I: and banll: is supported on 'thebridge supported bearingzstructui'es $32., 244', 545? described; in, detail hereinaboven In: otlrenmordsgthe main fu'nction of thezadjustab ly positioned extension 32A of flange SZ-is not: to carry :a load but to provide an adjustmentzwhereby thexdistanceybetween faces [0B and; I IB Tot thewave: guide may be altered. at the difierentasectionsizArthrough F along the wave guiderin :suchra :mannerrthat' the cross section maycb'e made 1 eunitormi 'or otherwise. as required throughoutrthe length .of; thewave guide. Such adjiistments ofvthe;extension"32A, accomplished by raddustmentrof: the set-screws,- I I-I' and-locking screw fizfl is in a direction perpendicular to the direction in which the clearances 2(132 I: are adjustedby' theofisetgshaftslor cranks 143;

The radiustably positioned extensions 132A are formed: by slitting flange: -;3 I, 32; tov :allow easy moyement ofa the; free-end thus -formedby the see-screw I H It-isnoted that there is r such an adjustable flange; 32AM;- eachone of-rthestations A-eFsorthat the adjustment may be-made-where needed It. is-.-thus-zapparent-that when the actuating ban lIwis-recipmcated 1inkst0-,-r8l are rotated aboutv anadiustable-ax-is rcorresponding tothe axis'of-bolta "19$?! I' l =(Figure- 7) to impart a reciprooation to the movable wave guidemember II: inuther direction t-indicated-by the arrow- 13, it being rememberedthat longitudinal movement of such guide member :II'inthe: directionofi itsax-is is-preuented by the centrally disposed guideblock tii (Figures-10- and-l2l= Imconventionat manner; conventional angle dataacoupling". capacitonand blanker' switch units iZBWFigure ,8) may be associated with theemovable wave guidevmemberr-I I to; provide sychronization of cathode ray-beam sweeps, andforother DUIIJQSES'JT W-hiie: the-particular;embodimentsxof the present'inventinn: ibave been-shown and described, it will be obviousrtothose. skilled in the;:art: that changes-and modificationsmay be made without departingfromthis'invention in its broader aspects and, therefore; the aiminthe appended claims is to cover all such changes and modifications as fall within the true spirit andscop'e of this invention'.

' I'claimr 1. In a variable wave guide, structure adapted to propagateultra-high frequency energy; andarrangedito-feed a plurality-of spaced dipoles; 'an elongatedmemberforming a relatively stationary portion ofsaid wave guide through which por- 'tions of said spaced dipoles extend to serve as spaced pickup ,probes for: energy propagated,- :as

internal cross-section of said .wave :guide being variable toalterthe apparent wave lengthof such "radiationto -:thereby change the.- .relative phase atiwhichzthedipoles are ted-toprcducea change in direction of the total energy ,radiatedzztrom allofsaid dipoles, said elongated member loaving:;pai-rs of support surfaces spaced transversely thereof,ia plurality of bridge structures releasably mounted on-correspond-ing :pairs of said support suriaceaza movable wave guide member cooperatively associated with saidfirstwave guide memher to form therewith the internal space of. the

Waveguide within which said radiation is .propagained,v an :adjustably positionedcrankimember'on eachpisaid bridge structures, and. said movable wave guidamember being movntedfor movement onisaid crank member. r

a variable wave guide structure adapted to :propagate ultra-high frequency energy and arrangedto feed a plurality of spaced-dipoles, said spaced dipoles each having a portion thereof extending within said wave guide to serve as spaced. pickup probes for energy propagated as radiation'vvithin said wave guide structure, the internalcross-section of said wave guidestructurebeing variable'to alter the apparent'wave length or" such radiation to thereby change the relative phase at which the dipoles are fed'to producea change in direction of the'total' energy radiated from all of the dipoles, said waveguide structure including an elongated member having a zpairx'of internally formedi'langes on opposite Walls thereof extending substantially parallel :in the longitudinal direction of said elongated member, a movable wave guideseotion cooperatively associated; with said elongated member to form a variable cross=section 'Wave guide; a bridge structurehaving each of its ends releasably and adjustably mounted on said flanges,a crank member adjustably'positioned xuni-said bridge structure, said movable wave "guide section .being mounted for movement on said crank member, at least a portion of one of said flangesbeing supported "as a cantilever on saidv elongated member, said movable wave guide section being supported on the free end of said cantilever, and means disposed between the free end of said cantilever and said elongated member to adjust the position of "said cantilever with respect-to said elongated member to thereby adjust the position'ofsaid movable wave guide section and cross-sectional area of said Wave guide.

3. In a variable wave guide structure adapted to propagate ultra-high frequency energy and arranged to feed a plurality of spaced" dipoles, said spaced dipoles having at least 'a portion thereof extending into said wave guide to serve as pickup probes for energy propagated as radiation within said wave guide structure; the internal cross-section of said guide structure being variable to alter the apparent Wave length of said radiation to thereby change the relative phase at which the *dipoles are-fed to produce a change in direction of the total energy-radiated from allof the dipoles,- said variablewave guide structurecomprising? a relatively stationary elongated" wave guide member, said stationary wave guidemember having cantilever supporting members'at-difierent sections along its'length, the free ends of said cantilever'supporting members-being movable to adjusted positions with 'respec-t to said stationary Wave guide member, a movable waveguide member cooperatively asseest tes ciated with respect to the first mentioned stationary wave guide member to form said variable wave guide structure, said movable wave guide member being supported on said cantilever supporting members, and means for adjusting and maintaining in adjusted position said free ends of said cantilever supporting members to thereby adjustably position said movable wave guide member with respect to said stationary wave guide member to align said movable wave guide member with respect to the stationary wave guide member, a bridge member having opposite ends thereof releasably secured to said relatively stationary guide member, a crank member adjustably positioned on said bridge member, and said movable guide member being mounted for movement on said crank member.

4. In a variable wave guide structure adapted to propagate ultra-high frequency energy and arranged to feed a plurality of spaced dipoles, said spaced dipoles having at least a portion thereof extending into said wave guide to serve as pickup probes for energy propagated as radiation within said wave guide structure, the internal cross-section of said guide structure being vari-- able to alter the apparent wave length of said radiation to thereby change the relative phase at which the dipoles are fed to produce a change in direction of the total energy radiated from all of the dipoles, said wave guide structure comprising: a relatively stationary wave guide member and a movable guide member cooperating therewith, a plurality of supporting elements releasably mounted on said stationary guide member at points therealong, crank members adjustably positioned on said supporting elements, said movable guide member being movable on said crank members, and cooperating wear-resistant surfaces disposed between said crank members and said movable guide member.

5. In a variable wave guide structure adapted to propagate ultra-high frequency energy and arranged to feed'a plurality of spaced dipoles, said spaced dipoles having at least a portion thereof extending into said wave guide to serve as pickup probes for energy propagated as radiation within said wave guide structure, the internal cross-section of said guide structure being variable to alter the apparent wave length of said radiation to thereby change the relative phase at which the dipoles are fed to produce a change in direction of the total energy radiated from all of the dipoles, said wave guide structure comprising: a relatively stationary wave guide member having at least a pair of spaced supporting members thereon, a relatively movable wave guide section cooperatively associated with said stationary guide member to provide a wave guide of varying cross-sectional area, a bridge structure releasably supported on said supporting members, spacers of predetermined thickness between said bridge structure and said supporting members to adjust the position of said bridge structure with respect to said stationary guide member, a crank member adjustably positioned on said bridge structure, and means supporting said movable guide member on said crank member for movement thereon.

6. In a variable wave guide structure adapted to propagate ultra-high frequency energy and arranged to feed a plurality ofspaced dipoles, said spaced dipoles having at least a portion thereof extending into said wave guide to serve as pickup probes for energy propagated as radiation within said waveguide structure, the internal cross-section of said guide structure being var- 1o iable to alter the apparent wave length of said radiation to therebychange the relative phase at which the dipoles are fed to produce a change in direction of the total energy radiated from all of the dipoles, said waveguide structure comprising: a relatively stationary wave guide mem-' ber having mounted thereon at least two spaced supporting members, one of said members being adjustably positioned with respect to said wave guide, means for adjusting said one supporting member and maintaining said one supporting member in adjusted position, a relatively move able guide member cooperatively associated with said stationary guide member to form a variable cross-sectional wave guide therewith, a bridge structure mounted on said supporting members, a crank member adjustably positioned on said bridge structure, and means mounting said movmember for moveable wave guideon said crank ment thereon.

7. In a variable wave guide structure adapted thereof extending into said wave guide to serve'as pickup probes for energy propagated as radiation within said wave guide structure, the internal cross-section of said guide structure being variable to alter the apparent wave length of said radiation to thereby change the relative phase at which the dipoles are fed to produce a change in direction of the total energy radiated from all of the dipoles, said wave guide structure comprising: a relatively stationary wave guide member, a relatively movable cooperating wave guide member to provide said guide structure of varying cross-sectional area, a longitudinally movable bar extending substantially the length of said wave guide and parallel to the longitudinal axis of the wave guide, said relatively movable guide member being mounted for movement on said stationary guide member in a direction perpendicular to the longitudinal axis of the guide, said bar member being pivotally attached to said relatively movable guide member, an adjustable supporting member on said stationary'guide member, a pivotal connection between said bar and said adjustable supporting member, a bridge member releasably secured to said stationary guide member, crank means adjustably posi- 8. In a variable wave guide structure adapted to propagate ultra-high frequency energy and arranged to feed 'a plurality of spaced dipoles, said spaced dipoles having at least a, portion thereof extending into said wave guide to serve as pickup probes for energy propagated as radiation within said Wave guide structure, the internal cross-section of said guide structure being variable to alter the apparent wavelength of said radiation to thereby change the relative phase at which thedipol es are fed, to produce a change in direction of the total energy radiated from all of the dipoles, a relatively stationary wave guide member, at least a pair of spaced supporting members on said stationary guide member, a bridge structure releasably mounted on said spaced supporting members, an adjustably positioned element mounted on said bridge structure, a relatively movable cooperating wave guide section movably mounted on said adjustably positioned element to provide said variable wave guide, a relatively movable cooperating Wave guide section; morablv mounted; uni-said bridge structure, saidbridgestructure being adjustable in. a first; dir ction, alcn itud m able bar member r tending substantiallyparallel to thedirection of said wave guide,;meansarranged to guide. said movable wave guide sectionin aydirectionperpendicular to the direction of said' wave; guide-,- a pivoted link-connected bar .to said movable wave guide section, a support on said stationary guide section adjustable in ..adirection;-perpendicular to said-first direction, and saidbarmember; bein pivotallymounted on said adjustablesupport.

9. In avariable wave guide structureadapted to propagate .ultra-highg frequency. energy and arranged to feeda. plurality of spac vd pole i said spaced dipoles having; at; leastga portion thereof extending into. said wave; uide; t.o;-.ser;ve as pickup probesifor; ener vaprena a ed. as;radia-. tion" within. said wave: guide; structure-,-v the internal cross-section of said guide structure; being: variable to. alter :the apparent: waye length. of said; radiation to thereby change the relative phase at which the dipoles are fedgtoproilucea change in: direction of, the total energy radiated from, all of the dipoles, said wave, uide. structure; comprising:; a; relatively stationary wave guide section, and .a cooperating. relatively .movable wave guide section, means. arran ed. to uide. the movement-of. said movable section in. a; direction substantially perpendicular to; the; longitudinal axis of said wave guide, a pluralityflofiindependently adjustable supporting: members mountedon said relatively stationary wave guide, member. and along its length, a lon itu inally .-m0vable bar member, movable, substantially parallel to the longitudinalaxis, of: said wave uide; link; means connecting said; bar to. said; movable wave guide section and to; said. adjustable supporting; mem: bers, a'plurality, of bridgexmembers releasablysupported at theirv endsv with-respect: to. saidrstal i tionary waveguide section, adjustablypositioned elements mounted on each. .of said bridge members and adapted to at-least partially supportzsaid movable wave: guidesection iorlmovementptherean acterized by the fact that-saidplurality. of; bridge members are releasablymounted and; are adjust.- able in position.

11. In a variablewave guide structure: adapted:

prising: a relatively stationary-guide member, a

relatively movable wave guidemember cooperatively associated with said stationary guide-member to provide'a wave guide with a variable rectangular cross-sectional area, each of; said'wave guide ,members havin cooperating I L -shaped portions with .an end of-a leg ofone portion;

spaced from the adjacent leg ofthe other coop-- crating portionby a distance termed the bclearance,- a supporting member. releasably: secured to said stationary wave-guidev membenan adjustablypositioned element mounted onsaid sup t n e means. moun in saidme r:

i0. Theinventionqdefinedin. .claim;..9, char- 12 able a e. u de member or m vement onsaid adiu b v: pos tioned element whereby said: f b" clearance is adjusted inaccordance .withrthe pos sition of said adiustabl positioned element.

12. In a variable Wave guide, structure adapted to propagate ultra-high frequency energy lan elongated member forming arelativelystationary portion of. said-wave guide structureiitheinternal cross-sectionv of. said: waveqguidenbeing:

variable to alter the. apparent"wayeiilength ofs radiation propagated :therein, said elongated,

member having pairs of support suriaees spaced transversely thereof, a pluralityof. bridge structures releasably' mounted on: corresponding pairs: of said support-surfaces, a movable; wavezguide member; cooperatively associated with said; first; wave guide member to forms therewith: the internal space .Ofithe wave. guide within-,whichisaid radiationis propagated, an adj-ustably positioned crank member ongsaid bridge-member; and said: movable waveguide member being: mounted :for; movement on'said crank'member.

13. In a variablewave guide structureeadapted to propagate ultra-hi h; frequency ener.gy, the internal cross-section of 'said Wave guide structure being variable; to" alter-I gtheqapparentwave length. of the ultra-high frequency-energypropagated therein,- said Wave guide structure including, an: elongated member having: a pair: of internally jiormed flanges on opposite walls thereof extending substantially parallel 'inpthe longitudinal direction of said-elongated: member, a movable wave; guide: section, cooperatively; associated with said: elongatedmember to. form; a variable cross-section wave guide; aibridgestructure releasably and adjustablyxmounted on said' flanges, a crank :member: adjustably; positioned onsaid bridgestructure, said;movab1e wave guide section being mounted for movement; on;.sai'dt crank member, at.leastsa;portion.of :one of said flanges being supported" as acantileveryon said elongated member, said movablewaveguide section being supported on .the free' end of-said cantilever; and means 3 disposed: between the free end of said cantilever and said, elongated member to. adjust'the position of said cantilever with respect to said elongated member .to. thereby adjust the position of'said movable wave guidesection; and the erossesectional area-s ofysaid. wave;

a id

14., In, a variable wave guide-structure adapted t pr pa te. ultra-h gh, re uency .ener vuas radiation, .the, internal cross-sectionof said guide structurc: being variable to alter:.-'the apparent, wave lengthof said radiation, saidvariable wave wave. guide member; to formsaid;variable-wave;

guide; structure: said: movable wavea guide meme benbeing supported onsaid cantilever. supporting members, and means; for: adjusting and maintaining in; adjusted position ,said; free: ends: of

said cantilever v supporting. members -to thereby adjustably position said movable-wave gguide:

member with respect to: said: stationarywwave. guide member. to align, said moyable;guide member with respect to the stationary-guide memher, a :bridgemember having opposite endsthereof releasably secured to said relatively stationary guide member, a crank member adjustably positioned on said bridge member, and said movable guide member being mounted for movement on said crank member.

15. In a variable wave guide structure adapted to propagate high frequency energy as radiation, the internal cross-section of said guide structure being variable to alter the apparent wave length of said radiation, said wave guide structure comprising: a relatively stationary guide member, a relatively movable wave guide member cooperatively associated with said stationary guide member to provide a wave guide with a variable rectangular cross-sectional area, each of said wave guide members having cooperative L-shaped portions with an end of a leg of one portion spaced from the adjacent leg of the other cooperating portion by a distance termed the b clearance, a supporting member releasably secured to said stationary wave guide member, an

adjustably positioned element mounted on said REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,811,508 Klages June 23, 1931 2,309,298 Bickel Jan. 26, 1943 2,433,368 Johnson Dec. 30, 1947 2,480,208 Alvarez Aug. 30, 1949 OTHER REFERENCES Radar System Engineering, by Ridenour, Radiation Laboratories Series, vol. 1 pages 291 to 294. a 

